Fig. 3.

a The distribution of fitness of random solutions for three different values of the parameter K _L. For small values of K _L corresponding to little space on the cell surface the random solutions are sharply peaked around a high fitness value converting well over 90 % of nutrient into growth. For K _L=0.5 and K _L=5000 random solutions peak at much lower fitness. b The fitness of 650000 random parameters as a function of the capacity of the uptake system. Each dot in this figure represents a simulation where parameters were chosen randomly and uniformly from the range [0,15] except for the value of K _L chosen randomly from the range [0,1]. The slight horizontal lines visible correspond to solutions that take up the second nutrient only (at 1/3) and the first nutrient only (at 2/3). All simulations here show solutions grown in absence of competition